Exemple #1
0
func InitDriver(job *engine.Job) engine.Status {
	var (
		network        *net.IPNet
		enableIPTables = job.GetenvBool("EnableIptables")
		icc            = job.GetenvBool("InterContainerCommunication")
		ipMasq         = job.GetenvBool("EnableIpMasq")
		ipForward      = job.GetenvBool("EnableIpForward")
		bridgeIP       = job.Getenv("BridgeIP")
		fixedCIDR      = job.Getenv("FixedCIDR")
	)

	if defaultIP := job.Getenv("DefaultBindingIP"); defaultIP != "" {
		defaultBindingIP = net.ParseIP(defaultIP)
	}

	bridgeIface = job.Getenv("BridgeIface")
	usingDefaultBridge := false
	if bridgeIface == "" {
		usingDefaultBridge = true
		bridgeIface = DefaultNetworkBridge
	}

	addr, err := networkdriver.GetIfaceAddr(bridgeIface)
	if err != nil {
		// If we're not using the default bridge, fail without trying to create it
		if !usingDefaultBridge {
			return job.Error(err)
		}
		// If the bridge interface is not found (or has no address), try to create it and/or add an address
		if err := configureBridge(bridgeIP); err != nil {
			return job.Error(err)
		}

		addr, err = networkdriver.GetIfaceAddr(bridgeIface)
		if err != nil {
			return job.Error(err)
		}
		network = addr.(*net.IPNet)
	} else {
		network = addr.(*net.IPNet)
		// validate that the bridge ip matches the ip specified by BridgeIP
		if bridgeIP != "" {
			bip, _, err := net.ParseCIDR(bridgeIP)
			if err != nil {
				return job.Error(err)
			}
			if !network.IP.Equal(bip) {
				return job.Errorf("bridge ip (%s) does not match existing bridge configuration %s", network.IP, bip)
			}
		}
	}

	// Configure iptables for link support
	if enableIPTables {
		if err := setupIPTables(addr, icc, ipMasq); err != nil {
			return job.Error(err)
		}
	}

	if ipForward {
		// Enable IPv4 forwarding
		if err := ioutil.WriteFile("/proc/sys/net/ipv4/ip_forward", []byte{'1', '\n'}, 0644); err != nil {
			job.Logf("WARNING: unable to enable IPv4 forwarding: %s\n", err)
		}
	}

	// We can always try removing the iptables
	if err := iptables.RemoveExistingChain("DOCKER", iptables.Nat); err != nil {
		return job.Error(err)
	}

	if enableIPTables {
		_, err := iptables.NewChain("DOCKER", bridgeIface, iptables.Nat)
		if err != nil {
			return job.Error(err)
		}
		chain, err := iptables.NewChain("DOCKER", bridgeIface, iptables.Filter)
		if err != nil {
			return job.Error(err)
		}
		portmapper.SetIptablesChain(chain)
	}

	bridgeNetwork = network
	if fixedCIDR != "" {
		_, subnet, err := net.ParseCIDR(fixedCIDR)
		if err != nil {
			return job.Error(err)
		}
		log.Debugf("Subnet: %v", subnet)
		if err := ipallocator.RegisterSubnet(bridgeNetwork, subnet); err != nil {
			return job.Error(err)
		}
	}

	// https://github.com/docker/docker/issues/2768
	job.Eng.Hack_SetGlobalVar("httpapi.bridgeIP", bridgeNetwork.IP)

	for name, f := range map[string]engine.Handler{
		"allocate_interface": Allocate,
		"release_interface":  Release,
		"allocate_port":      AllocatePort,
		"link":               LinkContainers,
	} {
		if err := job.Eng.Register(name, f); err != nil {
			return job.Error(err)
		}
	}
	return engine.StatusOK
}
Exemple #2
0
// Allocate an external port and map it to the interface
func AllocatePort(job *engine.Job) engine.Status {
	var (
		err error

		ip            = defaultBindingIP
		id            = job.Args[0]
		hostIP        = job.Getenv("HostIP")
		hostPort      = job.GetenvInt("HostPort")
		containerPort = job.GetenvInt("ContainerPort")
		proto         = job.Getenv("Proto")
		network       = currentInterfaces.Get(id)
	)

	if hostIP != "" {
		ip = net.ParseIP(hostIP)
		if ip == nil {
			return job.Errorf("Bad parameter: invalid host ip %s", hostIP)
		}
	}

	// host ip, proto, and host port
	var container net.Addr
	switch proto {
	case "tcp":
		container = &net.TCPAddr{IP: network.IP, Port: containerPort}
	case "udp":
		container = &net.UDPAddr{IP: network.IP, Port: containerPort}
	default:
		return job.Errorf("unsupported address type %s", proto)
	}

	//
	// Try up to 10 times to get a port that's not already allocated.
	//
	// In the event of failure to bind, return the error that portmapper.Map
	// yields.
	//

	var host net.Addr
	for i := 0; i < MaxAllocatedPortAttempts; i++ {
		if host, err = portmapper.Map(container, ip, hostPort); err == nil {
			break
		}
		// There is no point in immediately retrying to map an explicitly
		// chosen port.
		if hostPort != 0 {
			job.Logf("Failed to allocate and map port %d: %s", hostPort, err)
			break
		}
		job.Logf("Failed to allocate and map port: %s, retry: %d", err, i+1)
	}

	if err != nil {
		return job.Error(err)
	}

	network.PortMappings = append(network.PortMappings, host)

	out := engine.Env{}
	switch netAddr := host.(type) {
	case *net.TCPAddr:
		out.Set("HostIP", netAddr.IP.String())
		out.SetInt("HostPort", netAddr.Port)
	case *net.UDPAddr:
		out.Set("HostIP", netAddr.IP.String())
		out.SetInt("HostPort", netAddr.Port)
	}
	if _, err := out.WriteTo(job.Stdout); err != nil {
		return job.Error(err)
	}

	return engine.StatusOK
}